Check the listing for details. Small Preamplifier Preamp 6.35mm Plug Acoustic Guitar Preamplifier Enduring. Condition: New, Made in China. Listed at 19.87 USD. Features: Small preamplifier with impedance matching function for acoustic guitars. Supports 2-band EQ(BASS & TREBLE) and volumes adjusting. 6.35mm plug for connecting musical instrument and 6.35mm output plug for connecting guitar amplifier. It can also turn your home speaker into a guitar amplifier, allowing you to experience the pleasure of music performing. ABS material and compact size, durable and light weight, convenient to carry around. Specifications: Material: ABS Length: about 9.24cm/3.64inch Package Includes: 1Pc Small Preamplifier note: Please allow 1-2cm errors due to manual measurement, make sure that you not mind before you order. Due to difference between different monitors, the picture may not reflect the actual color of the item.